CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (unaudited) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2017 |
Sep. 30, 2016 |
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| Statement of Comprehensive Income [Abstract] | ||||
| Net income (loss) | $ 189,156 | $ 33,919 | $ 359,743 | $ (79,444) |
| Available-for-sale securities: | ||||
| Unrealized holding gains (losses), net of tax effect | 490 | (404) | (354) | (1,729) |
| Reclassification of realized transactions, net of tax effect | 0 | 7 | 0 | 89 |
| Defined benefit plans: | ||||
| Actuarial gains (losses) related to defined benefit pension plans, net of tax benefit of $2,311 $742, $1,385 and $3,745, respectively | 618 | (1,525) | (3,496) | (8,330) |
| Reclassification of realized transactions, net of tax effect | 213 | 0 | 416 | 0 |
| Change in net foreign currency translation adjustment | 0 | 454 | 0 | (2,569) |
| Other comprehensive income (loss), net of tax effect | 1,321 | (1,468) | (3,434) | (12,539) |
| Comprehensive income (loss) | $ 190,477 | $ 32,451 | $ 356,309 | $ (91,983) |
| X | ||||||||||
- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount after tax and reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after tax, before reclassification adjustment, of (increase) decrease in accumulated other comprehensive income of defined benefit plan, that has not been recognized in net periodic benefit cost (credit). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after tax, of reclassification adjustment from accumulated other comprehensive (income) loss for net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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